In a typical managed care facility for large animals such as horses, cows, etc., stalls are provided for occupancy by one or more animals at a time. A critical element of the stall is the flooring or bedding material, as animals spend many hours in a stall as a place for feeding and resting. Stall floors are typically dirt or concrete or, more recently, rubberized mats. Traditionally, straw or hay is distributed over the flooring to provide a softer surface and some very limited absorption of animal waste. In fact, straw and hay are not very absorbent, do not have adequate cushioning, and after mixing with animal waste become very slippery. Stall floors lined with organic materials such as straw or hay provide a breeding ground for various fungi which can cause respiratory and hoof infections, and induce allergic reactions in animals and humans. Furthermore, straw and hay do not perform any deodorizing or odor reducing function. Additives such as hydrated lime have been used with straw and hay as an ammonia/odor control agent. Lime has the disadvantages of high toxicity and is therefore relatively hazardous, low relative ammonia removal and high relative pH/high alkalinity, rendering the discarded stall material unsuitable for use as a fertilizer. Another disadvantage of straw and hay is the large amount of dust produced when these materials are applied to stall floors. This dust is inhaled by the animals causing irritation to the respiratory tract, making them more susceptible to the harmful effects of ammonia inhalation. This is particularly harmful to young animals that spend much of their time laying on stall floors where the dust accumulates. Dust is also unsanitary and hazardous and to the breeding and birthing processes.
Alternatively, a number of different materials, organic and inorganic, have been proposed for use as animal bedding material. Among these materials are cardboard, shredded paper such as recycled newsprint, wood shavings and mixtures of these materials. However, a number of disadvantages arise from use of these alternative materials. For instance, shredded paper is quickly saturated with animal urine and solid waste. It becomes matted and heavy and thus difficult to remove from the stall. Bedding material made from wood shavings, on the other hand, provides support and comfort, but has limited absorption characteristics and can contribute to fungal growth. Wood shavings are also slow to biodegrade and thus are unsuitable for use as fertilizer. An additional disadvantage of wood shavings is that the individual pieces get tangled in the hair, mane and tail of horses and other animals, making cleaning and grooming arduous.
An additional shortcoming of these prior art animal bedding materials is that they do not impede ammonia production in stalls where animals are housed. Even in small concentrations, ammonia can pose a health problem to animals. It has been shown that atmospheric ammonia is damaging to the respiratory tract. Even relatively low concentrations of ammonia can diminish airway defense mechanisms, making animals more vulnerable to pneumonia and asthma-like symptoms, leading to a higher incidence and increased severity of pneumonia, particularly in young animals. Lower weight gains have been observed in animals kept in stalls with ammonia concentrations as low as 25 ppm. Moreover, these materials offer no odor masking or odor reduction properties. The odors also attract flies and other insects which can carry disease and further stress the animals.
U.S. Pat. No. 5,209,186 describes an absorbent animal bedding material of nodules of cellulose material made from paper pulp produced from waste paper. These nodules have a smooth, hard, porous surface and resist breakage during use and handling. However, this material does not support the weight of large animals like horses and cows and creates dust when crushed. The nodules are crushed by the weight of these large animals, substantially reducing the amount of support and cushion provided by the bedding material. Also, this material is not easily or economically produced and requires numerous manufacturing steps and expensive mixing and heating equipment. Like the materials described above, this animal bedding material does not reduce ammonia production or odor.
U.S. Pat. No. 5,372,314 discloses an animal bedding material produced by mixing finely shredded cellulose material with calcium oxide and water to form a slurry. The slurry is then neutralized by mixing it with diatomaceous earth or a non-swelling clay and dried to form the animal bedding material. This animal bedding material is absorbent, but does not inhibit ammonia production and provides no relief from the unpleasant odor produced from animal waste.
U.S. Pat. Nos. 5,195,465 and 5,352,780 each describe a litter material made from compacted cellulose which has been formed into pellets and flaked. Both of these patents suggest adding fungicides, coloring agents, insecticides and herbicides to the flaked material to extend the life of the litter and reduce bacterial and fungal growth. However, neither patent offers a solution to the odor and ammonia production problems associated with other prior art animal bedding materials.
It has also been suggested in U.S. Pat. Nos. 5,133,296 and 5,265,561 to combine waste cardboard and wood pallets to make animal bedding material. However, the addition of the wood to the cardboard substantially decreases the biodegradability of this material making the bedding material essentially useless as fertilizer after it has become saturated with animal waste. Although wood chips are still used on stall floors, they must be kept separate from straw or hay for disposal as recycling fertilizer. Compost haulers will not accept stall waste which includes wood chips. Stall waste disposal is a critical issue, particularly with large animal care facilities such as zoos, racetracks, and horse farms. A stall material which cannot be economically disposed of cannot be used. This fact eliminates any material which contains wood or any other slow degrading material. Thus, a stall material is needed that performs hygienic and ergonomic functions in the stall, and a biodegradable fertilizing function in waste form has not been provided. Like the previously described prior art animal bedding materials, this approach offers no solution to the odor and ammonia production problem associated with conventional animal bedding materials.